Chitin,distinguished by its nitrogen-rich acetamido and amino groups,imparts a distinctive cationic nature,enabling chitin to have indispensable features in various applications.Despite its significant promise in the ...Chitin,distinguished by its nitrogen-rich acetamido and amino groups,imparts a distinctive cationic nature,enabling chitin to have indispensable features in various applications.Despite its significant promise in the textile industry,particularly for sustainable and functional fabric applications,the practical utilization of chitin fibers remains constrained by insufficient mechanical strength.The degree of deacetylation(DD),a key molecular-level structural determinant,has not been adequately addressed in previous studies despite its critical role in influencing chitin properties across multiple scales.In this study,a deacetylation-mediated design strategy was used to achieve enhanced mechanical performance coupled with multifunctional efficacy using an aqueous KOH/urea solution dissolution system.We prepared a series of deacetylated chitins with different DD values and systematically studied the effect of deacetylation on the multiple-scale structure of regenerated fibers,such as intermolecular interactions and chain orientation at the molecular level,and the aggregation behavior of chitin nanofibers within the gel-state and dried fibers at the micro/nano scale.To achieve an enhanced mechanical performance coupled with multifunctional efficacy by relying on an aqueous KOH/urea solution dissolution system.Moreover,deacetylation enhances intermolecular interactions,resulting in densified internal structures and improved fiber orientation.Concomitantly,it augmented the antimicrobial functionality of the fibers.This deacetylation-mediated design strategy provides a deeper understanding of the structure and properties of regenerated chitin and advances the utility of chitin in strong and sustainable fibers.展开更多
Trans-(-)-ε-viniferin(ε-viniferin)has antioxidative and anti-inflammatory effects.It also has neuroprotective effects in Huntington's disease by activating the SIRT3/LKB1/AMPK signaling pathway;however,it remain...Trans-(-)-ε-viniferin(ε-viniferin)has antioxidative and anti-inflammatory effects.It also has neuroprotective effects in Huntington's disease by activating the SIRT3/LKB1/AMPK signaling pathway;however,it remains unknown whetherε-viniferin also has a neuroprotective role in Parkinson's disease.A Parkinson's disease cell model was induced by exposing SH-SY5 Y cells to 3.0μM rotenone for 24 hours,and cells were then treated with 1.0μMε-viniferin for 24 hours.Treatment withε-viniferin upregulated SIRT3 expression,which promoted FOXO3 deacetylation and nuclear localization.ε-Viniferin also increased ATP production and decreased reactive oxygen species production.Furthermore,ε-viniferin treatment alleviated rotenone-induced mitochondrial depolarization and reduced cell apoptosis,and restored the expression of mitochondrial homeostasis-related proteins.However,when cells were transfected with SIRT3 or FOXO3 shRNA prior to rotenone andε-viniferin treatment,these changes were reversed.The results from the present study indicate thatε-viniferin enhances SIRT3-mediated FOXO3 deacetylation,reduces oxidative stress,and maintains mitochondrial homeostasis,thus inhibiting rotenone-induced cell apoptosis.ε-Viniferin may therefore be a promising treatment strategy for Parkinson's disease.展开更多
Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypoth-esized that the combination ...Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypoth-esized that the combination of these two approaches could result in enhanced regeneration. Rats with right sciatic nerve injury were subjected to deacetyl chitin conduit bridging combined with electrical stimulation （0.1 ms, 3 V, 20 Hz, for 1 hour）. At 6 and 12 weeks after treatment, nerve conduction velocity, myelinated axon number, ifber diameter, axon diameter and the thickness of the myelin sheath in the stimulation group were better than in the non-stimulation group. The results indicate that deacetyl chitin conduit bridging combined with temporary electrical stimu-lation can promote peripheral nerve repair.展开更多
AIM: To explore the effects of IκBα SUMOylation and NF-κB p65 deacetylation on NF-κB p65 activity induced by high glucose in cultured human lens epithelial cells(HLECs).METHODS: HLECs(SRA01/04) were cultured with ...AIM: To explore the effects of IκBα SUMOylation and NF-κB p65 deacetylation on NF-κB p65 activity induced by high glucose in cultured human lens epithelial cells(HLECs).METHODS: HLECs(SRA01/04) were cultured with 5.5, 25, and 50 mmol/L glucose media for 24 h, and with 50 mmol/L glucose media for 0, 12, and 24 h respectively. SUMO1 and SIRT1 expressions were detected by reverse transcriptionpolymerase chain reaction(RT-PCR) and Western blot(WB). IκBα and NF-κB p65 expressions were detected by WB. With NAC, DTT, MG132 or Resveratrol(RSV) treatment, SUMO1 and SIRT1 expressions were detected by WB. Protein expression localizations were examined by immunofluorescence and co-immunofluorescence. The effects of SUMO1 or SIRT1 overexpression, as well as MG132 and RSV, on the nuclear expression and activity of IκBα and NF-κB p65 were analyzed by immunoblot and dual luciferase reporter gene assay.RESULTS: SUMO1 and SIRT1 expressions were influenced by high glucose in mRNA and protein levels, which could be blocked by NAC or DTT. SUMO1 was down-regulated by using MG132, and SIRT1 was up-regulated under RSV treatment. IκBα nuclear expression was attenuated and NF-κB p65 was opposite under high glucose, while IκBα and NF-κB p65 location was transferred to the nucleus. SUMO1 or SIRT1 overexpression and MG132 or RSV treatment affected the nuclear expression and activity of IκBα and NF-κB p65 under high glucose condition.CONCLUSION: IκBα SUMOylation and NF-κB p65 deacetylation affect NF-κB p65 activity in cultured HLECs under high glucose, and presumably play a significant role in controlling diabetic cataract.展开更多
Epigenetic mechanisms,such as DNA methylation and histone modifications(e.g.,acetylation and deacetylation),are strongly implicated in the carcinogenesis of various malignancies.During transcription,the expression and ...Epigenetic mechanisms,such as DNA methylation and histone modifications(e.g.,acetylation and deacetylation),are strongly implicated in the carcinogenesis of various malignancies.During transcription,the expression and functionality of coding gene products are altered following the histone acetylation and deacetylation.These processes are regulated by histone acetyltransferases(HATs)and histone deacetylases(HDACs),respectively.HDAC inhibitors(HDACis)have been developed as promising therapeutic agents,to limit exposure to traditional and toxic chemotherapies and offer more alternatives for some specific malignant diseases with limited options.Mechanistically,these agents affect many intracellular pathways,including cell cycle arrest,apoptosis and differentiation,and their mechanism of action mainly depends on the type of cancer.Currently,five HDACis have been approved for the treatment of several hematological malignancies(e.g.,T-cell lymphoma subtypes and multiple myeloma);while,many of them are tested for further therapeutic indications in solid tumors(e.g.,colorectal,thyroid,breast,lung and pancreatic cancer).Herein,we review the literature and gather all available evidence,from in vitro and in vivo data to clinical trial results,that recognizes the antitumor activity of HDACis on pheochromocytomas and paragangliomas;and supports their clinical implementation in the treatment of these rare neuroendocrine tumors at metastatic setting.展开更多
Chitin and chitosan films were prepared by solution casting method. Chitosan specimens used in this study were deacetylated by 50.4%, 69.2%, 85.5% and 96.3%. Their water content, protein adhesion ability, cytocompatib...Chitin and chitosan films were prepared by solution casting method. Chitosan specimens used in this study were deacetylated by 50.4%, 69.2%, 85.5% and 96.3%. Their water content, protein adhesion ability, cytocompatibility, cell adhesion ability, in vitro and vivo degradability and biocompatibility were evaluated. Results indicated that with the degree of deacetylation （DD） between 50% and 70%, the chitosan showed higher water content. The higher the DD, the stronger protein adhesion ability the chitosan had. All the films have good cytocompatibility and the films with higher DD have better cell adhesion ability. Chitin films degraded more rapidly than others, which disappeared in 2 to 4 weeks after they were implanted in subcutaneous tissue and musculature. Their inflammatory reaction became weaker as the films degraded. As the DD got higher, the films degraded slower. The films of DD 85.5% and DD 90.3% even didn＇t disappeared in 12 weeks after they were implanted. Their inflammatory reaction was mild at the beginning of degradation, and became severe in 4 to 8 weeks, then weaken at last. This basic result can be very helpful for tissue engineering.展开更多
The acetyl ester plays an important role for protection of the hydroxyl groups in carbohydrates synthesis.In the present study,we described an efficient deprotection of acetyl group of pentacyclic triterpenoid by usin...The acetyl ester plays an important role for protection of the hydroxyl groups in carbohydrates synthesis.In the present study,we described an efficient deprotection of acetyl group of pentacyclic triterpenoid by using methanolic ammonia in THF solution.Good selectivity for cleaving gal-C2-OAc group of 3β-hydroxy-olean-12-en-28-oic acid 28-N-2,3,4,6-tetra-O-acetyl-β-D-galactopyranoside(3) was achieved in the presence of methanolic ammonia within 4 h at low temperature(-60℃) in a yield of 56%.The reaction disclosed here provides a new method for the synthesis of C2 selective modified carbohydrates,which is more useful than conventional synthesis procedure that usually requires many steps including temporary regioselective protection and deprotection.When the reaction temperature was increased from -60℃ to room temperature,the cleavage of the other three acetyl groups of galactose in an order of C4-OAc>C3-OAc>C6-OAc was observed.Based on this study,a plausible route for the deacetylation reaction has been proposed.展开更多
The shift from skotomorphogenesis to photomorphogenesis,a developmental transition in seed plants,in-volves dramatic proteomic changes.Lysine acetylation(Lys-Ac)is an evolutionarily conserved and recog-nized post-tran...The shift from skotomorphogenesis to photomorphogenesis,a developmental transition in seed plants,in-volves dramatic proteomic changes.Lysine acetylation(Lys-Ac)is an evolutionarily conserved and recog-nized post-translational modification that plays a crucial role in plant development.However,its role in seedling deetiolation remains unclear.In this study,we conducted a comparative lysine acetylomic anal-ysis of etiolated Arabidopsis seedlings before and after red(R)light irradiation,uncovering that exposure to R light mainly led to protein lysine deacetylation during seedling deetiolation.Phytochrome A(phyA),a unique far-red(FR)light photoreceptor,was deacetylated at lysine 65(K65)when etiolated seedlings were moved to light.This residue is a critical ubiquitination site that regulates phyA stability.Moreover,K65 deacetylation facilitates phyA ubiquitination and 26s proteasome-mediated degradation,and is required for the function of phyA in FR light signaling and seedling photomorphogenesis.Furthermore,we identified a plant-specific lysine deacetylase HDT2 that interacts with and deacetylates phyA in the nu-cleus to promote its ubiquitination and degradation during seedling deetiolation.Genetic analysis revealed that HDT2 is critical for phyA-mediated photomorphogenic growth.Taken together,these findings reveal that lysine deacetylation of phyA by HDT2 plays a crucial role in modulating phyA turnover in response to light,suggesting that Lys-Ac might be central to the reprogramming of plants for photomorphogenic growth.展开更多
Wheat root systems undergo dynamic and adaptive changes to mitigate adverse effects through sophisticated regulatory mechanisms under drought stress.Elucidating and utilizing these mechanisms is highly important for b...Wheat root systems undergo dynamic and adaptive changes to mitigate adverse effects through sophisticated regulatory mechanisms under drought stress.Elucidating and utilizing these mechanisms is highly important for breeding drought-resistant wheat varieties.Here,we identify histone deacetylase TaHDA8 as a critical component that negatively regulates wheat root elongation and drought tolerance.Under drought stress,TaHDA8 could be finely tuned to alleviate its inhibition of root elongation,thereby improving wheat adaptation to water deficit.Interestingly,reduction in TaHDA8 protein levels de-represses the DNA-binding ability of TaAREB3,a positive regulator of root elongation and drought tolerance,which depends on the retention of acetylation at K248 and K281 residues.The restored DNA binding of TaAREB3 to the promoter of TaKOR1 upregulates its expression,thereby promoting root elongation by enhancing cell proliferation in the root meristem.Further studies revealed that natural variations in the TaKOR1 promoter determine the differences in TaAREB3 binding,and wheat germplasm with TaHDA8–TaAREB3–TaKOR1 regulatory module has been widely selected.Collectively,this study reveals how a lysine deacetylase regulates drought-responsive root development via non-histone deacetylation,providing genetic resources for improving root architecture and breeding drought-resilient wheat varieties.展开更多
The infiltration of glioblastoma multiforme(GBM)is predominantly characterized by diffuse spread,contributing significantly to therapy resistance and recurrence of GBM.In this study,we reveal that microtubule deacetyl...The infiltration of glioblastoma multiforme(GBM)is predominantly characterized by diffuse spread,contributing significantly to therapy resistance and recurrence of GBM.In this study,we reveal that microtubule deacetylation,mediated through the downregulation of fibronectin type III and SPRY domain-containing 1(FSD1),plays a pivotal role in promoting GBM diffuse infiltration.FSD1 directly interacts with histone deacetylase 6(HDAC6)at its second catalytic domain,thereby impeding its deacetylase activity onα-tubulin and preventing microtubule deacetylation and depolymerization.This inhibitory interaction is disrupted upon phosphorylation of FSD1 at its Ser317 and Ser324 residues by activated CDK5,leading to FSD1 dissociation from microtubules and facilitating HDAC6-mediatedα-tubulin deacetylation.Furthermore,increased expression of FSD1 or interference with FSD1 phosphorylation reduces microtubule deacetylation,suppresses invasion of GBM stem cells,and ultimately mitigates tumor infiltration in orthotopic GBM xenografts.Importantly,GBM tissues exhibit diminished levels of FSD1 expression,correlating with microtubule deacetylation and unfavorable clinical outcomes in GBM patients.These findings elucidate the mechanistic involvement of microtubule deacetylation in driving GBM cell invasion and offer potential avenues for managing GBM infiltration.展开更多
Wheat is a staple food globally.Grain size substantially affects yield by influencing grain weight.Only a few genes associated with grain yield have been cloned in wheat by omics strategies and map-based cloning.Lecti...Wheat is a staple food globally.Grain size substantially affects yield by influencing grain weight.Only a few genes associated with grain yield have been cloned in wheat by omics strategies and map-based cloning.Lectin receptor-like kinases(LecRLKs),a plant-specific RLK subfamily,are involved in plant development,seed germination,hormone signaling,and response to abiotic and biotic stresses[1].A recent study has indicated an association of LecRLKs with grain yield[2].However,the role of wheat LecRLKs in the regulation of grain size remains poorly understood.展开更多
The anthracnose caused by Colletotrichum gloeosporioides poses a significant threat to the global mango(Mangifera indica L.)fruit industry.Although histone deacetylases(HDACs)are well recognized to be involved in plan...The anthracnose caused by Colletotrichum gloeosporioides poses a significant threat to the global mango(Mangifera indica L.)fruit industry.Although histone deacetylases(HDACs)are well recognized to be involved in plant immunity,the role of HDAC-mediated nonhistone deacetylation in the fruit immune response remains elusive.In the present study,MiHDA3,an HDAC from the RPD3/HDA1 subfamily,was identified as a candidate for regulating mango resistance based on the greatest induction of MiHDA3 in response to infection of C.gloeosporioides among the 19 tested HDAC genes.Transient overexpression of MiHDA3 in mango fruit strengthened the disease resistance by enhancing the activities of defense-related enzymes(phenylalanine ammonia-lyase(PAL)andβ-1,3-glucanase(GLU))and upregulating the expression levels of MiPAL and MiGLU.These increases occurred concomitantly with increased accumulation of local H_(2)O_(2),a critical signaling molecule.The opposite effects on resistance and H_(2)O_(2) production were observed in MiHDA3-silenced mango fruit.Physiological assays revealed that exogenous H_(2)O_(2) treatment suppressed anthracnose development in mango fruit after inoculation with C.gloeosporioides,whereas treatment with diphenylene iodonium,an inhibitor of endogenous H_(2)O_(2) generation,exacerbated disease symptoms.Furthermore,the mango catalase 1(MiCAT1),a redox homeostasis-related protein,was confirmed to negatively regulate the resistance of mango fruit to C.gloeosporioides by catalyzing the decomposition of H_(2)O_(2).Mechanistic investigations revealed that MiHDA3-mediated deacetylation of MiCAT1 at lysine residues K227 and K233 reduced the enzymatic activity and protein stability of MiCAT1,contributing to enhanced resistance in mango fruit.Collectively,these findings highlight that the functional interplay between HDACs and catalases can modulate the immune response in post-harvest fruits,and reveal a novel mechanism by which HDACs enhance mango disease resistance through the deacetylation of nonhistone proteins and the regulation of their biochemical functions.展开更多
tHistone deacetylases(HDACs)are proteases that play a key role in chromosome structural modification and gene expression regulation,and the involvement of HDACs in can-cer,the nervous system,and the metabolic and immu...tHistone deacetylases(HDACs)are proteases that play a key role in chromosome structural modification and gene expression regulation,and the involvement of HDACs in can-cer,the nervous system,and the metabolic and immune system has been well reviewed.Our understanding of the function of HDACs in the vascular system has recently progressed,and a significant variety of HDAC inhibitors have been shown to be effective in the treatment of vascular diseases.However,few reviews have focused on the role of HDACs in the vascular sys-tem.In this study,the role of HDACs in the regulation of the vascular system mainly involving endothelial cells and vascular smooth muscle cells was discussed based on recent updates,and the role of HDACs in different vascular pathogenesis was summarized as well.Furthermore,the therapeutic effects and prospects of HDAC inhibitors were also addressed in this review.展开更多
文摘Chitin,distinguished by its nitrogen-rich acetamido and amino groups,imparts a distinctive cationic nature,enabling chitin to have indispensable features in various applications.Despite its significant promise in the textile industry,particularly for sustainable and functional fabric applications,the practical utilization of chitin fibers remains constrained by insufficient mechanical strength.The degree of deacetylation(DD),a key molecular-level structural determinant,has not been adequately addressed in previous studies despite its critical role in influencing chitin properties across multiple scales.In this study,a deacetylation-mediated design strategy was used to achieve enhanced mechanical performance coupled with multifunctional efficacy using an aqueous KOH/urea solution dissolution system.We prepared a series of deacetylated chitins with different DD values and systematically studied the effect of deacetylation on the multiple-scale structure of regenerated fibers,such as intermolecular interactions and chain orientation at the molecular level,and the aggregation behavior of chitin nanofibers within the gel-state and dried fibers at the micro/nano scale.To achieve an enhanced mechanical performance coupled with multifunctional efficacy by relying on an aqueous KOH/urea solution dissolution system.Moreover,deacetylation enhances intermolecular interactions,resulting in densified internal structures and improved fiber orientation.Concomitantly,it augmented the antimicrobial functionality of the fibers.This deacetylation-mediated design strategy provides a deeper understanding of the structure and properties of regenerated chitin and advances the utility of chitin in strong and sustainable fibers.
基金supported by the National Natural Science Foundation of China,Nos.81771271(to JF),81801710(to YM)the Science and Technology Project Funds from Education Department of Liaoning Province of China,Nos.LK2016022(to SZ),LK2016021(to YM)。
文摘Trans-(-)-ε-viniferin(ε-viniferin)has antioxidative and anti-inflammatory effects.It also has neuroprotective effects in Huntington's disease by activating the SIRT3/LKB1/AMPK signaling pathway;however,it remains unknown whetherε-viniferin also has a neuroprotective role in Parkinson's disease.A Parkinson's disease cell model was induced by exposing SH-SY5 Y cells to 3.0μM rotenone for 24 hours,and cells were then treated with 1.0μMε-viniferin for 24 hours.Treatment withε-viniferin upregulated SIRT3 expression,which promoted FOXO3 deacetylation and nuclear localization.ε-Viniferin also increased ATP production and decreased reactive oxygen species production.Furthermore,ε-viniferin treatment alleviated rotenone-induced mitochondrial depolarization and reduced cell apoptosis,and restored the expression of mitochondrial homeostasis-related proteins.However,when cells were transfected with SIRT3 or FOXO3 shRNA prior to rotenone andε-viniferin treatment,these changes were reversed.The results from the present study indicate thatε-viniferin enhances SIRT3-mediated FOXO3 deacetylation,reduces oxidative stress,and maintains mitochondrial homeostasis,thus inhibiting rotenone-induced cell apoptosis.ε-Viniferin may therefore be a promising treatment strategy for Parkinson's disease.
基金funded by National Program on Key Basic Research Project of China(973 Program),No.2014CB542200the National Natural Science Foundation of China,No.31171150,31271284,30801169+2 种基金the Chinese Educational Ministry New Century Excellent Talent Support Project,No.BMU20110270the Beijing City Science&Technology New Star Classification,No.2008A010the Ministry of Education New Teachers of Institutions of Higher Learning Doctoral Fund,No.20070001780
文摘Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypoth-esized that the combination of these two approaches could result in enhanced regeneration. Rats with right sciatic nerve injury were subjected to deacetyl chitin conduit bridging combined with electrical stimulation （0.1 ms, 3 V, 20 Hz, for 1 hour）. At 6 and 12 weeks after treatment, nerve conduction velocity, myelinated axon number, ifber diameter, axon diameter and the thickness of the myelin sheath in the stimulation group were better than in the non-stimulation group. The results indicate that deacetyl chitin conduit bridging combined with temporary electrical stimu-lation can promote peripheral nerve repair.
基金Supported by the National Natural Science Foundation of China(No.81170836, No.81570838)
文摘AIM: To explore the effects of IκBα SUMOylation and NF-κB p65 deacetylation on NF-κB p65 activity induced by high glucose in cultured human lens epithelial cells(HLECs).METHODS: HLECs(SRA01/04) were cultured with 5.5, 25, and 50 mmol/L glucose media for 24 h, and with 50 mmol/L glucose media for 0, 12, and 24 h respectively. SUMO1 and SIRT1 expressions were detected by reverse transcriptionpolymerase chain reaction(RT-PCR) and Western blot(WB). IκBα and NF-κB p65 expressions were detected by WB. With NAC, DTT, MG132 or Resveratrol(RSV) treatment, SUMO1 and SIRT1 expressions were detected by WB. Protein expression localizations were examined by immunofluorescence and co-immunofluorescence. The effects of SUMO1 or SIRT1 overexpression, as well as MG132 and RSV, on the nuclear expression and activity of IκBα and NF-κB p65 were analyzed by immunoblot and dual luciferase reporter gene assay.RESULTS: SUMO1 and SIRT1 expressions were influenced by high glucose in mRNA and protein levels, which could be blocked by NAC or DTT. SUMO1 was down-regulated by using MG132, and SIRT1 was up-regulated under RSV treatment. IκBα nuclear expression was attenuated and NF-κB p65 was opposite under high glucose, while IκBα and NF-κB p65 location was transferred to the nucleus. SUMO1 or SIRT1 overexpression and MG132 or RSV treatment affected the nuclear expression and activity of IκBα and NF-κB p65 under high glucose condition.CONCLUSION: IκBα SUMOylation and NF-κB p65 deacetylation affect NF-κB p65 activity in cultured HLECs under high glucose, and presumably play a significant role in controlling diabetic cataract.
文摘Epigenetic mechanisms,such as DNA methylation and histone modifications(e.g.,acetylation and deacetylation),are strongly implicated in the carcinogenesis of various malignancies.During transcription,the expression and functionality of coding gene products are altered following the histone acetylation and deacetylation.These processes are regulated by histone acetyltransferases(HATs)and histone deacetylases(HDACs),respectively.HDAC inhibitors(HDACis)have been developed as promising therapeutic agents,to limit exposure to traditional and toxic chemotherapies and offer more alternatives for some specific malignant diseases with limited options.Mechanistically,these agents affect many intracellular pathways,including cell cycle arrest,apoptosis and differentiation,and their mechanism of action mainly depends on the type of cancer.Currently,five HDACis have been approved for the treatment of several hematological malignancies(e.g.,T-cell lymphoma subtypes and multiple myeloma);while,many of them are tested for further therapeutic indications in solid tumors(e.g.,colorectal,thyroid,breast,lung and pancreatic cancer).Herein,we review the literature and gather all available evidence,from in vitro and in vivo data to clinical trial results,that recognizes the antitumor activity of HDACis on pheochromocytomas and paragangliomas;and supports their clinical implementation in the treatment of these rare neuroendocrine tumors at metastatic setting.
基金the China"863"High-technology Development Program under contract No.2003AA625050.
文摘Chitin and chitosan films were prepared by solution casting method. Chitosan specimens used in this study were deacetylated by 50.4%, 69.2%, 85.5% and 96.3%. Their water content, protein adhesion ability, cytocompatibility, cell adhesion ability, in vitro and vivo degradability and biocompatibility were evaluated. Results indicated that with the degree of deacetylation （DD） between 50% and 70%, the chitosan showed higher water content. The higher the DD, the stronger protein adhesion ability the chitosan had. All the films have good cytocompatibility and the films with higher DD have better cell adhesion ability. Chitin films degraded more rapidly than others, which disappeared in 2 to 4 weeks after they were implanted in subcutaneous tissue and musculature. Their inflammatory reaction became weaker as the films degraded. As the DD got higher, the films degraded slower. The films of DD 85.5% and DD 90.3% even didn＇t disappeared in 12 weeks after they were implanted. Their inflammatory reaction was mild at the beginning of degradation, and became severe in 4 to 8 weeks, then weaken at last. This basic result can be very helpful for tissue engineering.
基金supported by the National Natural Science Foundation of China(Nos.21572015,21877007,81703540 and 21702007)China Postdoctoral Science Foundation(No.2018M631796)+2 种基金Technology Plan Foundation of Liaoning Province(No.20170520063)Chinese Medicine Related Scientific Research Project of Dalian(No.17Z2013)the open funding of the State Key Laboratory of Phytochemistry and Plant Resources in West China。
文摘The acetyl ester plays an important role for protection of the hydroxyl groups in carbohydrates synthesis.In the present study,we described an efficient deprotection of acetyl group of pentacyclic triterpenoid by using methanolic ammonia in THF solution.Good selectivity for cleaving gal-C2-OAc group of 3β-hydroxy-olean-12-en-28-oic acid 28-N-2,3,4,6-tetra-O-acetyl-β-D-galactopyranoside(3) was achieved in the presence of methanolic ammonia within 4 h at low temperature(-60℃) in a yield of 56%.The reaction disclosed here provides a new method for the synthesis of C2 selective modified carbohydrates,which is more useful than conventional synthesis procedure that usually requires many steps including temporary regioselective protection and deprotection.When the reaction temperature was increased from -60℃ to room temperature,the cleavage of the other three acetyl groups of galactose in an order of C4-OAc>C3-OAc>C6-OAc was observed.Based on this study,a plausible route for the deacetylation reaction has been proposed.
基金supported by grants from the National Natural Science Foundation of China(32371326 and 32070551)the Science and Technology Projects in Guangzhou(E3330900-01)the Youth Innovation PromotionAssociation,CAs(201860).
文摘The shift from skotomorphogenesis to photomorphogenesis,a developmental transition in seed plants,in-volves dramatic proteomic changes.Lysine acetylation(Lys-Ac)is an evolutionarily conserved and recog-nized post-translational modification that plays a crucial role in plant development.However,its role in seedling deetiolation remains unclear.In this study,we conducted a comparative lysine acetylomic anal-ysis of etiolated Arabidopsis seedlings before and after red(R)light irradiation,uncovering that exposure to R light mainly led to protein lysine deacetylation during seedling deetiolation.Phytochrome A(phyA),a unique far-red(FR)light photoreceptor,was deacetylated at lysine 65(K65)when etiolated seedlings were moved to light.This residue is a critical ubiquitination site that regulates phyA stability.Moreover,K65 deacetylation facilitates phyA ubiquitination and 26s proteasome-mediated degradation,and is required for the function of phyA in FR light signaling and seedling photomorphogenesis.Furthermore,we identified a plant-specific lysine deacetylase HDT2 that interacts with and deacetylates phyA in the nu-cleus to promote its ubiquitination and degradation during seedling deetiolation.Genetic analysis revealed that HDT2 is critical for phyA-mediated photomorphogenic growth.Taken together,these findings reveal that lysine deacetylation of phyA by HDT2 plays a crucial role in modulating phyA turnover in response to light,suggesting that Lys-Ac might be central to the reprogramming of plants for photomorphogenic growth.
基金funded by the National Natural Science Foundation of China(32130078,32441061)the National Key Research and Development Program of China(2022YFF1001604)+1 种基金Chinese Universities Scientific Fund(2024TC188)Young-scholar program of China Agricultural University-Bayannur Research Institute(2024BYNECAU009).
文摘Wheat root systems undergo dynamic and adaptive changes to mitigate adverse effects through sophisticated regulatory mechanisms under drought stress.Elucidating and utilizing these mechanisms is highly important for breeding drought-resistant wheat varieties.Here,we identify histone deacetylase TaHDA8 as a critical component that negatively regulates wheat root elongation and drought tolerance.Under drought stress,TaHDA8 could be finely tuned to alleviate its inhibition of root elongation,thereby improving wheat adaptation to water deficit.Interestingly,reduction in TaHDA8 protein levels de-represses the DNA-binding ability of TaAREB3,a positive regulator of root elongation and drought tolerance,which depends on the retention of acetylation at K248 and K281 residues.The restored DNA binding of TaAREB3 to the promoter of TaKOR1 upregulates its expression,thereby promoting root elongation by enhancing cell proliferation in the root meristem.Further studies revealed that natural variations in the TaKOR1 promoter determine the differences in TaAREB3 binding,and wheat germplasm with TaHDA8–TaAREB3–TaKOR1 regulatory module has been widely selected.Collectively,this study reveals how a lysine deacetylase regulates drought-responsive root development via non-histone deacetylation,providing genetic resources for improving root architecture and breeding drought-resilient wheat varieties.
基金supported by the National Key Research and Development Program of China(2022YFA1303000,2017YFA0505602)the National Natural Science Foundation of China(81872408,81872153).
文摘The infiltration of glioblastoma multiforme(GBM)is predominantly characterized by diffuse spread,contributing significantly to therapy resistance and recurrence of GBM.In this study,we reveal that microtubule deacetylation,mediated through the downregulation of fibronectin type III and SPRY domain-containing 1(FSD1),plays a pivotal role in promoting GBM diffuse infiltration.FSD1 directly interacts with histone deacetylase 6(HDAC6)at its second catalytic domain,thereby impeding its deacetylase activity onα-tubulin and preventing microtubule deacetylation and depolymerization.This inhibitory interaction is disrupted upon phosphorylation of FSD1 at its Ser317 and Ser324 residues by activated CDK5,leading to FSD1 dissociation from microtubules and facilitating HDAC6-mediatedα-tubulin deacetylation.Furthermore,increased expression of FSD1 or interference with FSD1 phosphorylation reduces microtubule deacetylation,suppresses invasion of GBM stem cells,and ultimately mitigates tumor infiltration in orthotopic GBM xenografts.Importantly,GBM tissues exhibit diminished levels of FSD1 expression,correlating with microtubule deacetylation and unfavorable clinical outcomes in GBM patients.These findings elucidate the mechanistic involvement of microtubule deacetylation in driving GBM cell invasion and offer potential avenues for managing GBM infiltration.
基金funded by the National Key Research and Development Program(2023YFD1200403)the Henan Natural Science Foundation(24HASTIT055,252300421246,and 25A210020)of China.
文摘Wheat is a staple food globally.Grain size substantially affects yield by influencing grain weight.Only a few genes associated with grain yield have been cloned in wheat by omics strategies and map-based cloning.Lectin receptor-like kinases(LecRLKs),a plant-specific RLK subfamily,are involved in plant development,seed germination,hormone signaling,and response to abiotic and biotic stresses[1].A recent study has indicated an association of LecRLKs with grain yield[2].However,the role of wheat LecRLKs in the regulation of grain size remains poorly understood.
基金financially supported by the Natural Science Foundation of Hainan Province,China(Grant No.324RC456)National Natural Science Foundation of China(Grant No.32460786)+2 种基金South China Botanical Garden,Chinese Academy of Sciences(Grant No.QNXM-202306)the Guangdong Science and Technology Plan Project(Grant No.2023B1212060046)the Foundation of Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement,South China Botanical Garden,Chinese Academy of Sciences(Guangzhou,China)。
文摘The anthracnose caused by Colletotrichum gloeosporioides poses a significant threat to the global mango(Mangifera indica L.)fruit industry.Although histone deacetylases(HDACs)are well recognized to be involved in plant immunity,the role of HDAC-mediated nonhistone deacetylation in the fruit immune response remains elusive.In the present study,MiHDA3,an HDAC from the RPD3/HDA1 subfamily,was identified as a candidate for regulating mango resistance based on the greatest induction of MiHDA3 in response to infection of C.gloeosporioides among the 19 tested HDAC genes.Transient overexpression of MiHDA3 in mango fruit strengthened the disease resistance by enhancing the activities of defense-related enzymes(phenylalanine ammonia-lyase(PAL)andβ-1,3-glucanase(GLU))and upregulating the expression levels of MiPAL and MiGLU.These increases occurred concomitantly with increased accumulation of local H_(2)O_(2),a critical signaling molecule.The opposite effects on resistance and H_(2)O_(2) production were observed in MiHDA3-silenced mango fruit.Physiological assays revealed that exogenous H_(2)O_(2) treatment suppressed anthracnose development in mango fruit after inoculation with C.gloeosporioides,whereas treatment with diphenylene iodonium,an inhibitor of endogenous H_(2)O_(2) generation,exacerbated disease symptoms.Furthermore,the mango catalase 1(MiCAT1),a redox homeostasis-related protein,was confirmed to negatively regulate the resistance of mango fruit to C.gloeosporioides by catalyzing the decomposition of H_(2)O_(2).Mechanistic investigations revealed that MiHDA3-mediated deacetylation of MiCAT1 at lysine residues K227 and K233 reduced the enzymatic activity and protein stability of MiCAT1,contributing to enhanced resistance in mango fruit.Collectively,these findings highlight that the functional interplay between HDACs and catalases can modulate the immune response in post-harvest fruits,and reveal a novel mechanism by which HDACs enhance mango disease resistance through the deacetylation of nonhistone proteins and the regulation of their biochemical functions.
基金supported by the National Natural Science Foundation of China(No.82103508,82203758)Natural Science Foundation of Shaanxi Province(China)(No.SZYKJCYC-2023-028)+3 种基金the Science and Technology Development Incubation Fund of Shaanxi Provincial People's Hospital,Shaanxi,China(No.2021YJY-21)the Project of Tangdu Hospital,the Air Force Medical University,Shaanxi,China(No.XJSXYW202130,XJSXYW-2023015,2021LCYJ019)the Project of Air Foce Medical University,Shaanxi,China(No.2022LC2227)the Talent Support Program of Shaanxi Provincial People's Hospital,Shaanxi,China(No.2022JY-38).
文摘tHistone deacetylases(HDACs)are proteases that play a key role in chromosome structural modification and gene expression regulation,and the involvement of HDACs in can-cer,the nervous system,and the metabolic and immune system has been well reviewed.Our understanding of the function of HDACs in the vascular system has recently progressed,and a significant variety of HDAC inhibitors have been shown to be effective in the treatment of vascular diseases.However,few reviews have focused on the role of HDACs in the vascular sys-tem.In this study,the role of HDACs in the regulation of the vascular system mainly involving endothelial cells and vascular smooth muscle cells was discussed based on recent updates,and the role of HDACs in different vascular pathogenesis was summarized as well.Furthermore,the therapeutic effects and prospects of HDAC inhibitors were also addressed in this review.
